Production of pilus-like filaments in Geobacter sulfurreducens in the absence of the type IV pilin protein PilA.

TitleProduction of pilus-like filaments in Geobacter sulfurreducens in the absence of the type IV pilin protein PilA.
Publication TypeJournal Article
Year of Publication2010
AuthorsKlimes A, Franks AE, Glaven RH, Tran H, Barrett CL, Qiu Y, Zengler K, Lovley DR
JournalFEMS Microbiol Lett
Volume310
Issue1
Pagination62-8
Date Published2010 Sep 1
ISSN1574-6968
KeywordsBacterial Adhesion, Fimbriae Proteins, Fimbriae, Bacterial, Gene Deletion, Geobacter, Glass, Microscopy, Electron, Transmission
Abstract

The pili of Geobacter sulfurreducens are of interest because of the apparent importance of the type IV pili in extracellular electron transfer. A strain of G. sulfurreducens, designated strain MA, produced many more pili than the previously studied DL-1 strain even though genome resequencing indicated that the MA and DL-1 genome sequences were identical. Filaments that looked similar to type IV pili in transmission electron micrographs were abundant even after the gene encoding PilA, the structural pilin protein, was deleted. The results of proteinase K treatment indicated that the filaments were proteinaceous. The simultaneous deletion of several genes encoding homologues of type II pseudopilins was required before the filaments were significantly depleted. The pilA-deficient MA strain attached to glass as well as the wild-type MA did, but strains in which three or four pseudopilin genes were deleted in addition to pilA had impaired attachment capabilities. These results demonstrate that there are several proteins that can yield pilin-like filaments in G. sulfurreducens and that some means other than microscopic observation is required before the composition of filaments can be unambiguously specified.

DOI10.1111/j.1574-6968.2010.02046.x
Alternate JournalFEMS Microbiol. Lett.
PubMed ID20629752